If you’re hurt in a car crash in Ontario, you can claim accident benefits from your own auto insurer—no matter who caused the collision. These benefits cover things like treatment and rehabilitation, some lost-income support, and (in more serious cases) attendant care. They are a separate, “no-fault” system that runs alongside any lawsuit you might bring against the at-fault driver.

The Minor Injury Guideline (MIG) is Ontario’s default no-fault Accident Benefits framework under the SABS for soft-tissue/whiplash-type injuries. Placement in the MIG caps medical/rehab funding at $3,500 through a standardized protocol. You can exit if credible medical evidence shows a non-minor diagnosis or a pre-existing condition expected to prevent maximal recovery within MIG limits^[1].

Many claims start in the MIG based on the insurer’s early read of the file. Getting out matters. It unlocks far higher funding and broader treatment options, the difference between a small rehab budget and the ability to pursue longer, more complex care plans.

MIG status also has spillover perception effects in any fault (tort) claim against the at-fault driver for pain and suffering. It doesn’t decide liability or damages—judges and juries aren’t bound by a plaintiff’s insurer’s MIG position—but it shapes negotiation optics. Staying in the MIG can be used by the defendant driver and their counsel to argue the injuries are modest. A well-supported exit (for example, based on concussion, chronic pain, psychological injury, or a pre-existing condition that slows recovery) can signal greater seriousness and move numbers. The legal standards are different, but the same medical record feeds both streams.

If there’s one issue that never cools down in Ontario accident benefits, it’s the MIG. The stakes are structural. The MIG caps funding and channels care into a narrow protocol. Applicants press to escape it. Insurers press to keep files within it. That friction—medical, legal, and procedural—produces a steady stream of Licence Appeal Tribunal (LAT) disputes and a body of case law that keeps evolving, especially around concussions, chronic pain, psychological impairments, pre-existing conditions, and notice compliance.

What follows is a practice-minded map of where the law actually is—and why the squeeze keeps tightening.

The burden and the evidence: who must prove what?

At the LAT, the applicant carries the burden to show, on a balance of probabilities, that injuries fall outside the MIG. That’s not new, but recent decisions keep underlining it and, more importantly, what kind of medical evidence meets the mark. Decisions such as HS vs. Aviva Insurance Canada, 2019 ONLAT 17-007384/AABS^[2] confirm the burden rests with the applicant. Later cases (e.g., Castro v Allstate Insurance, 2023 CanLII 101080 (ON LAT)^[3]) reiterate that bare complaints or ambiguous entries won’t do. There must be clear, qualified medical opinion linking symptoms to a diagnosis or functional limitation inconsistent with “minor injury.”

The flip side is that contemporaneous and qualified medical evidence is often decisive. A single “head injury” note can sometimes tip the balance (see Jolicoeur v RBC Insurance, 2020 CanLII 103478 (ON LAT)^[4]), but LAT members regularly discount late, speculative, or outside-expertise assertions. (See also Hughes v Intact Insurance Company, 2022 CanLII 53743 (ON LAT)^[5]).

Chronic pain: the foundational course-correction that still governs

The MIG’s definition doesn’t name chronic pain, and treating it as a “clinically associated sequelae” of sprains/strains was explicitly rejected in the seminal reconsideration decision in T.S. v Aviva General Insurance Canada, 2018 CanLII 83520 (ON LAT)^[6]. Executive Chair Lamoureux held that chronic pain is not captured by the MIG and cannot be swept in via “clinically associated sequelae.” That principle has been repeatedly followed.

Concussions: diagnosis-driven—and the diagnostician doesn’t have to be a neurologist

Two recent lines of cases show both edges of the sword. On one edge, where the medical record supports a concussion diagnosis, the MIG usually falls away. Gavey v Wawanesa Insurance, 2024 CanLII 77430 (ON LAT)^[7]accepted a family physician’s concussion opinion as sufficient to take the case out of the MIG. Mohammed v Economical Insurance Company, 2024 CanLII 123 (ON LAT)^[8] reached the same destination even though symptoms later resolved.

On the other edge, when the “concussion” rests on thin or late evidence, applicants lose the MIG fight. Dawkins v BelairDirect Insurance Company, 2024 CanLII 81222 (ON LAT)^[9] and Aus v Unifund, 2024 CanLII 69882 (ON LAT)^[10]both rejected removal where imaging and contemporaneous records didn’t support a clear concussion diagnosis. The thread through these cases is simple: the weight of early, qualified, and consistent medical evidence controls.

Psychological impairments: chronic pain plus psych often defeats the MIG—if the record is complete

Psychological injuries can also move a case out of the MIG, particularly when the records are thorough and contemporaneous and when assessors engage with the full medical file. Huber v Allstate Insurance Company of Canada, 2024 CanLII 41012 (ON LAT)^[11] is a clean example.The LAT found chronic pain plus psychological impairment exceeded the MIG once the missing treating records were considered and an insurer IE that ignored key materials was given little weight.

Pre-existing conditions: s.18(2) still matters, but you must prove impact on prognosis

The statutory exception for pre-existing conditions (s.18(2)^[12]) continues to be applied in a rigorously evidence-driven way. S.18(2) lets a claimant exit the MIG where a regulated health professional provides credible evidence that a pre-existing condition will prevent maximal recovery under the MIG, so the $3,500 cap doesn’t apply and higher med-rehab limits are available.

You need competent medical opinion that the pre-existing condition will prevent maximal recovery within the MIG’s parameters. Recent decisions emphasize that mere history isn’t enough. A claimant needs to tie the condition to prolonged recovery and functional impairment. See, for example, these cases for how adjudicators parse this showing:  Ji v Economical Insurance Company^[13], 2024 CanLII 13083 (ON LAT), Vegh v Unifund Assurance Company^[14]/em>, 2024 CanLII 6506 (ON LAT), Berat v Economical Insurance^[15], 2023 CanLII 72609 (ON LAT), and Brown v Co-operators General Insurance Company^[16], 2024 CanLII 54026 (ON LAT).

The procedural squeeze: s.38 notice compliance can decide the file

The MIG fight isn’t just medical. Section 38^[17] sets the rules for Treatment and Assessment Plans (OCF-18). The insurer must respond within 10 business days with clear reasons and IE rights, and if it fails to give proper, timely notice (including any MIG position), it can be barred from relying on the MIG and must fund the proposed treatment until compliant.

The LAT has repeatedly treated defective s.38 denials as outcome-shaping, sometimes barring reliance on the MIG and compelling payment for treatment until the defect is cured. M.F.Z. v Aviva Insurance Canada, 2017 CanLII 63632 (ON LAT)^[18] remains the go-to reconsideration decision on the consequences of non-compliant denial notices.

What all of this means in the trenches

For applicants, the way out of the MIG is paved early. Get a clear diagnosis (especially on concussion and psychological injury) from a qualified medical provider, lock down contemporaneous clinical notes, and show how symptoms translate into functional limits that don’t fit the MIG’s model. If you’re relying on s.18(2), make the doctor say the magic words, that the pre-existing condition is expected to prevent maximal recovery within MIG limits. When chronic pain is central, cite T.S. v Aviva and marry the diagnosis to function and treatment needs.

For insurers, adjust promptly and methodically. Use s.33^[19] early to secure all treating records before commissioning s.44^[20] IEs. Make sure your examiners actually review what you’ve obtained. And don’t let denials go out with boilerplate—M.F.Z. shows how s.38 missteps can swallow a MIG defence and force funding you didn’t budget for. Concussion disputes are now evidence cases. If you intend to challenge causation (e.g., minimal impact), get the right expertise. Otherwise Gavey/Mohammed-style records from family doctors will carry the day.

The Bottom Line

The MIG squeeze persists because the law demands proof tailored to diagnosis and function, and the LAT is increasingly unforgiving of thin records and procedural shortcuts. Chronic pain is not a minor injury (T.S.). Concussions will usually beat the MIG when credibly diagnosed (Gavey, Mohammed). Psychological impairments can do the same (Huber), and s.18(2) remains viable when pre-existing conditions are shown to derail MIG-level recovery (Ji, Vegh, Berat, Brown).

Do the evidentiary work up front, or the squeeze will do it for you—on costs, on entitlement, and on appeal.